Letrozole

Generic Name: letrozole

Aromatase Inhibitor [EPC]Over-the-Counter (OTC)

Brand Names:

Letrozole

11 DESCRIPTION Letrozole tablet USP for oral administration contains 2.5 mg of letrozole, a nonsteroidal aromatase inhibitor (inhibitor of estrogen synthesis). It is chemically described as 4,4'-(1H-1,2,4-Triazol-1-ylmethylene) dibenzonitrile, and its structural formula is Letrozole is a white to yellowish crystalline powder, practically odorless, freely soluble in dichloromethane, slightly soluble in ethanol, and practically insoluble in water.

Overview

11 DESCRIPTION Letrozole tablet USP for oral administration contains 2.5 mg of letrozole, a nonsteroidal aromatase inhibitor (inhibitor of estrogen synthesis). It is chemically described as 4,4'-(1H-1,2,4-Triazol-1-ylmethylene) dibenzonitrile, and its structural formula is Letrozole is a white to yellowish crystalline powder, practically odorless, freely soluble in dichloromethane, slightly soluble in ethanol, and practically insoluble in water.

Uses

1 INDICATIONS AND USAGE Letrozole tablet is an aromatase inhibitor indicated for: Adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer ( 1.1 ) Extended adjuvant treatment of postmenopausal women with early breast cancer who have received prior standard adjuvant tamoxifen therapy ( 1.2 ) First and second-line treatment of postmenopausal women with hormone receptor positive or unknown advanced breast cancer ( 1.3 ) 1.1 Adjuvant Treatment of Early Breast Cancer Letrozole tablets are indicated for the adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer.

Dosage

2 DOSAGE AND ADMINISTRATION Letrozole tablets are taken orally without regard to meals ( 2 ): Recommended dose: 2.5.mg once daily ( 2.1 ) Patients with cirrhosis or severe hepatic impairment: 2.5 mg every other day ( 2.5 , 5.3 ) 2.1 Recommended Dose The recommended dose of letrozole tablet is one 2.5 mg tablet administered once a day, without regard to meals. 2.2 Use in Adjuvant Treatment of Early Breast Cancer In the adjuvant setting, the optimal duration of treatment with letrozole is unknown. In both the adjuvant study and the post approval adjuvant study, median treatment duration was 5 years. Treatment should be discontinued at relapse [see Clinical Studies ( 14.1 )].

Side Effects

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling. Bone effects [see Warnings and Precautions ( 5.1 )] Increases in cholesterol [see Warnings and Precautions ( 5.2 )] Fatigue and Dizziness [see Warnings and Precautions ( 5.4 )] The most common adverse reactions (greater than 20%) were hot flashes, arthralgia; flushing, asthenia, edema, arthralgia, headache, dizziness, hypercholesterolemia, sweating increased, bone pain and musculoskeletal ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Accord Healthcare Inc. at 1-866-941-7875 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

Interactions

7 DRUG INTERACTIONS Tamoxifen Coadministration of letrozole and tamoxifen 20 mg daily resulted in a reduction of letrozole plasma levels of 38% on average (Study P015). Clinical experience in the second-line breast cancer trials (AR/BC2 and AR/BC3) indicates that the therapeutic effect of letrozole therapy is not impaired if letrozole is administered immediately after tamoxifen. Cimetidine A pharmacokinetic interaction study with cimetidine (Study P004) showed no clinically significant effect on letrozole pharmacokinetics. Warfarin An interaction study (P017) with warfarin showed no clinically significant effect of letrozole on warfarin pharmacokinetics. Other Anticancer Agents There is no clinical experience to date on the use of letrozole in combination with other anticancer agents.

Warnings

5 WARNINGS AND PRECAUTIONS Decreases in bone mineral density may occur. Consider bone mineral density monitoring ( 5.1 ) Increases in total cholesterol may occur. Consider cholesterol monitoring. ( 5.2 ) Fatigue, dizziness and somnolence may occur. Exercise caution when operating machinery ( 5.4 ) Embryo-Fetal Toxicity: Can cause fetal harm when administered to pregnant women. Obtain a pregnancy test in females of reproductive potential. Advise females of reproductive potential to use effective contraception ( 5.6 , 8.1 , 8.3 ) 5.1 Bone Effects Use of letrozole may cause decreases in bone mineral density (BMD). Consideration should be given to monitoring BMD. 4 CONTRAINDICATIONS Pregnancy: Letrozole can cause fetal harm [see Use in Specific Populations ( 8.1 )] . Pregnancy: Letrozole can cause fetal harm [see Use in Specific Populations ( 8.1 )] . Known hypersensitivity to the active substance, or to any of the excipients [see Adverse Reactions ( 6 )] .

Pregnancy

8.1 Pregnancy Risk Summary Based on postmarketing reports, findings from animal studies and the mechanism of action, letrozole can cause fetal harm and is contraindicated for use in pregnant women. In post-marketing reports, use of letrozole during pregnancy resulted in cases of spontaneous abortions and congenital birth defects; however, the data are insufficient to inform a drug-associated risk [see Contraindications ( 4 ), Warnings and Precautions ( 5.6 ), Adverse Reactions ( 6.2 ) and Clinical Pharmacology ( 12.1 )].

Storage

16 HOW SUPPLIED/STORAGE AND HANDLING Packaged in HDPE bottles and unit dose blister package. 2.5 mg tablets – yellow round, biconvex, film coated tablets imprinted with 'LT' on one side and plain on other side.

Frequently Asked Questions

What is Letrozole used for?

1 INDICATIONS AND USAGE Letrozole tablet is an aromatase inhibitor indicated for: Adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer ( 1.1 ) Extended adjuvant treatment of postmenopausal women with early breast cancer who have received prior standard adjuvant tamoxifen therapy ( 1.2 ) First and second-line treatment of postmenopausal women with hormone receptor positive or unknown advanced breast cancer ( 1.3 ) 1.1 Adjuvant Treatment of Early Breast Cancer Letrozole tablets are indicated for the adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer.

What are the side effects of Letrozole?

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling. Bone effects [see Warnings and Precautions ( 5.1 )] Increases in cholesterol [see Warnings and Precautions ( 5.2 )] Fatigue and Dizziness [see Warnings and Precautions ( 5.4 )] The most common adverse reactions (greater than 20%) were hot flashes, arthralgia; flushing, asthenia, edema, arthralgia, headache, dizziness, hypercholesterolemia, sweating increased, bone pain and musculoskeletal ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Accord Healthcare Inc. at 1-866-941-7875 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

Can I take Letrozole during pregnancy?

8.1 Pregnancy Risk Summary Based on postmarketing reports, findings from animal studies and the mechanism of action, letrozole can cause fetal harm and is contraindicated for use in pregnant women. In post-marketing reports, use of letrozole during pregnancy resulted in cases of spontaneous abortions and congenital birth defects; however, the data are insufficient to inform a drug-associated risk [see Contraindications ( 4 ), Warnings and Precautions ( 5.6 ), Adverse Reactions ( 6.2 ) and Clinical Pharmacology ( 12.1 )].

What are the important warnings for Letrozole?

5 WARNINGS AND PRECAUTIONS Decreases in bone mineral density may occur. Consider bone mineral density monitoring ( 5.1 ) Increases in total cholesterol may occur. Consider cholesterol monitoring. ( 5.2 ) Fatigue, dizziness and somnolence may occur. Exercise caution when operating machinery ( 5.4 ) Embryo-Fetal Toxicity: Can cause fetal harm when administered to pregnant women. Obtain a pregnancy test in females of reproductive potential. Advise females of reproductive potential to use effective contraception ( 5.6 , 8.1 , 8.3 ) 5.1 Bone Effects Use of letrozole may cause decreases in bone mineral density (BMD). Consideration should be given to monitoring BMD. 4 CONTRAINDICATIONS Pregnancy: Letrozole can cause fetal harm [see Use in Specific Populations ( 8.1 )] . Pregnancy: Letrozole can cause fetal harm [see Use in Specific Populations ( 8.1 )] . Known hypersensitivity to the active substance, or to any of the excipients [see Adverse Reactions ( 6 )] .

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Medical Disclaimer

This drug information is for educational purposes only and should not replace professional medical advice. Drug information is sourced from the FDA National Drug Code Directory and Structured Product Labeling. Always consult with a healthcare provider before starting, stopping, or changing any medication.